When a will has been admitted to probate, any person interested therein may at any time within three (3) months from the date the will was admitted to probate contest the same or the validity of the will. For that purpose he must file in the court in which the will was proved a sworn petition in writing containing his allegations, that evidence discovered since the probate of the will, the material facts of which must be set forth, shows:
1. That a will of a later date than the one proved by the decedent, revoking or changing the will, has been discovered, and is offered; or2. That some jurisdictional fact was wanting in the probate; or3. That the testator was not competent, free from duress, menace, fraud, or undue influence when the will allowed was made; or4. That the will was not duly executed and attested.Okla. Stat. tit. 58, § 61
R.L. 1910, § 6219; Amended by Laws 1953, HB 676, p. 233, § 6; Amended by Laws 1967, SB 37, c. 10, § 1, emerg. eff. 2/20/1967.